The Budget Committee chairman and 2012 GOP vice presidential nominee said Obama hasn't had to make tough decisions on vetoing legislation because Senate Majority Leader Harry Reid (D-Nev.) has shelved most of the bills sent over by the GOP-led House.

“Right now, Harry Reid is protecting the president from making difficult decisions,” Ryan said Thursday, “and I believe that we can unblock a number of things that should at least get to the president’s desk and make him make a decision.”

Obama has only vetoed legislation twice during his nearly six years in the Oval Office, though he has used the veto threat with regularity to batter House Republicans. But the president could begin racking up vetoes next year, if the Congress falls under complete GOP control.

Ryan said Republicans would have a two-pronged agenda if they win both chambers of Congress: send Obama bills that highlight the party’s contrast with Democrats ahead of 2016, while approving some small-bore legislation that could get signed into law.

“It will be a combination of contrasts and a combination of moving the ball incrementally in the right direction,” he said.

At the top of Republicans’ possible 2015 agenda: a bill paving the way for construction of the Keystone XL oil pipeline. Ryan also wants Republicans to make the Obama administration “stretch a little further in our direction” when it comes to reforming entitlements and the budget process.

Tax reform is another issue that could be revived in a GOP Congress. Senate Minority Leader Mitch McConnell (R-Ky.) said earlier this year he could envision a Republican House and Senate reaching a deal in 2015 to reduce rates and “make America more competitive.”

Ryan is poised to become a key player in the tax reform debate, as he’s expected to take over the House’s tax-writing Ways and Means Committee gavel from retiring Rep. Dave Camp (R-Mich.).

The Budget Committee chairman said the issue of “inversions” — where U.S. corporations buy foreign companies and move their headquarters abroad to avoid taxes — “adds a new sense of urgency” for tax reform.

“It will not die for my lack of trying,” Ryan said.

Ryan, who was calling from Wisconsin, has been crisscrossing the country this summer recess, promoting his new book, The Way Forward: Renewing the American Idea. Stops included Philadelphia; Orlando, Fla.; Oklahoma City and Denver, as well as the George W. Bush and Ronald Reagan presidential libraries.

The whirlwind 20-city book tour wasn’t all that different from the 2012 campaign, which Ryan described in detail in his book. The congressman found himself visiting some of the same cities he stumped in two years ago and catching up with some of the same people he met on the campaign trail.

"It was very similar to the campaign — except we stopped at stoplights," he said.

The highlight of the tour, he said, was hanging out with his former running mate Mitt Romney at an event in Chicago, where they both lightheartedly nudged each other to run for president. The night ended with Ryan dousing Romney with water for the charity ice-bucket challenge.

“We’ve become really good friends, and this was the first public event we have done since the election in 2012,” Ryan said. “To have a great evening with him, to top it off by dumping a bucket of ice on his head, that was definitely very memorable.”

Most observers don’t think a third run for the White House is in the cards for Romney, but he’s been polling well ahead of the pack in Iowa.

Asked if he was open to another Romney-Ryan ticket in 2016, Ryan didn’t miss a beat: “I’d do whatever Mitt would ask of me, including drive his campaign bus if he thought that was the way I could be the most useful.”

The new book and subsequent media blitz have set tongues wagging that Ryan could join what’s expected to be a crowded presidential primary field that is likely to include New Jersey Gov. Chris Christie, and Sens. Rand Paul (Ky.), Ted Cruz (Texas) and Marco Rubio (Fla.).

But Ryan has repeatedly said he’s still discussing a potential run with his family and won’t make a decision until 2015.

He said he feels fairly confident the Senate will flip to GOP control in November, given Obama’s sagging popularity, but he said “Democrats are putting up a very spirited fight.”

“I think they have headwinds and they are coming out swinging deep and early and raising a lot of money. They believe that is going to help them keep it close,” Ryan said.

“I just think most Americans are dissatisfied with the direction we’re headed,” he added. “There isn’t a negative campaign that can change that, so ultimately, I think we’re gonna be in a good position.”

As for the House, Ryan was more circumspect about predicting how many seats Republicans would pick up.

“I’m a policy guy. I don’t sit around and look at different polling data from different races,” he said. “Our goal is to get to 245, and we think it’s a realistic goal.”